An agricultural harvester known as a “combine” is historically termed such because it combines multiple harvesting functions with a single harvesting unit, such as picking, threshing, separating and cleaning. A combine includes a header which removes the crop from a field, and a feeder housing which transports the crop matter into a threshing rotor. The threshing rotor rotates within a perforated housing, which may be in the form of adjustable concaves, and performs a threshing operation on the crop to remove the grain. Once the grain is threshed it falls through perforations in the concaves and is transported to a grain pan. From the grain pan the grain is cleaned using a cleaning system, and is then transported to a grain tank onboard the combine. The cleaning system includes a cleaning fan which blows air through oscillating sieves to discharge chaff and other debris toward the rear of the combine. Non-grain crop material such as straw from the threshing section proceeds through a straw chopper and out the rear of the combine. When the grain tank becomes full, the combine is positioned adjacent a vehicle into which the grain is to be unloaded, and an unloading system, e.g., an unloading auger, on the combine is actuated to transfer the grain into the vehicle.
A typical header includes one or more cutters, e.g., cutter bars with reciprocating knives, which cut the crop material that is harvested from the field. Once the crop material is cut, a conveyor system, which is positioned rearwardly of the cutter(s), transports the crop material to the feeder housing. Modern headers generally have cutters and attachments which are specifically optimized to harvest a particular kind of crop material. For example, the header may include a rotating reel with tines or the like to sweep the crop material towards the cutter(s). Alternatively, the header may include snouts and row units instead of a rotating reel and cutter bar(s).
Generally, a header is rigidly mounted to the feeder housing of the agricultural vehicle. Rigidly attached headers typically function effectively under ideal operating conditions, such as level ground and ideal weather conditions. However, with respect to some larger headers and/or in less than ideal conditions, a rigid header may ineffectively gather the crop material. For example, if the ground has undulations or if the crop has fallen over (i.e. become “lodged”) the header may miss a portion of the crop material as it cannot respond to specific changes in terrain or crop conditions. Over the course of harvesting an entire field, a rigidly attached header may lead to significant header loss.
To overcome the disadvantages of rigidly mounted headers, some agricultural vehicles have incorporated a movably mounted header such that the elevation, roll, and/or pitch of the header may be adjusted, allowing the header to more aggressively harvest the crop material. A feeder housing may lift the header vertically. Lateral tilt cylinders may be incorporated to roll the header laterally (e.g., tilting left up/right down). An additional hydraulic cylinder may be added to control the pitch of the header (tilting fore/aft). Also, the header may adjust the position of the rotating reel and the angle of its cutter bar(s). For example, in the case of lodged crop material, a header may be lowered and tilted forwardly to pick up crop material which otherwise would have been left on the field. Hence, in various circumstances, including changes to vehicle inclination, ground undulation, or crop condition, a moveable header may greatly reduce header loss compared to a rigidly mounted header.
An operator is generally required to frequently measure, monitor, and adjust the crop cutting and gathering functions of the agricultural vehicle. To obtain an initial pitch angle for a moveable header, an operator may need to estimate or measure this pitch angle with a measuring device (e.g., protractor), relative to the ground and the specific drive tires or tracks of the header. Based from this initial pitch angle, the operator may manually make header pitch adjustments from within the cab or may physically adjust the face-plate adaptor of the feeder housing in order to respond to various operational changes. In addition to adjusting the header pitch, the operator will also monitor and adjust other parameters such as the position of the rotating reel, angle of the cutter bar(s), and the speed of the agricultural vehicle. This perpetual measuring, monitoring, and/or adjusting of the crop cutting and gathering functions may lead to operator fatigue.
What is needed in the art is an agricultural harvester that automates the measuring, monitoring and adjusting of the crop cutting and gathering functions so that the operator may concentrate on other machine functions.